1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3 * Copyright IBM Corp. 2001, 2006
4 * Author(s): Robert Burroughs
5 * Eric Rossman (edrossma@us.ibm.com)
6 *
7 * Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
8 * Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
9 */
10
11 #ifndef _ZCRYPT_CCA_KEY_H_
12 #define _ZCRYPT_CCA_KEY_H_
13
14 struct t6_keyblock_hdr {
15 unsigned short blen;
16 unsigned short ulen;
17 unsigned short flags;
18 };
19
20 /**
21 * mapping for the cca private ME key token.
22 * Three parts of interest here: the header, the private section and
23 * the public section.
24 *
25 * mapping for the cca key token header
26 */
27 struct cca_token_hdr {
28 unsigned char token_identifier;
29 unsigned char version;
30 unsigned short token_length;
31 unsigned char reserved[4];
32 } __packed;
33
34 #define CCA_TKN_HDR_ID_EXT 0x1E
35
36 #define CCA_PVT_USAGE_ALL 0x80
37
38 /**
39 * mapping for the cca public section
40 * In a private key, the modulus doesn't appear in the public
41 * section. So, an arbitrary public exponent of 0x010001 will be
42 * used, for a section length of 0x0F always.
43 */
44 struct cca_public_sec {
45 unsigned char section_identifier;
46 unsigned char version;
47 unsigned short section_length;
48 unsigned char reserved[2];
49 unsigned short exponent_len;
50 unsigned short modulus_bit_len;
51 unsigned short modulus_byte_len; /* In a private key, this is 0 */
52 } __packed;
53
54 /**
55 * mapping for the cca private CRT key 'token'
56 * The first three parts (the only parts considered in this release)
57 * are: the header, the private section and the public section.
58 * The header and public section are the same as for the
59 * struct cca_private_ext_ME
60 *
61 * Following the structure are the quantities p, q, dp, dq, u, pad,
62 * and modulus, in that order, where pad_len is the modulo 8
63 * complement of the residue modulo 8 of the sum of
64 * (p_len + q_len + dp_len + dq_len + u_len).
65 */
66 struct cca_pvt_ext_crt_sec {
67 unsigned char section_identifier;
68 unsigned char version;
69 unsigned short section_length;
70 unsigned char private_key_hash[20];
71 unsigned char reserved1[4];
72 unsigned char key_format;
73 unsigned char reserved2;
74 unsigned char key_name_hash[20];
75 unsigned char key_use_flags[4];
76 unsigned short p_len;
77 unsigned short q_len;
78 unsigned short dp_len;
79 unsigned short dq_len;
80 unsigned short u_len;
81 unsigned short mod_len;
82 unsigned char reserved3[4];
83 unsigned short pad_len;
84 unsigned char reserved4[52];
85 unsigned char confounder[8];
86 } __packed;
87
88 #define CCA_PVT_EXT_CRT_SEC_ID_PVT 0x08
89 #define CCA_PVT_EXT_CRT_SEC_FMT_CL 0x40
90
91 /**
92 * Set up private key fields of a type6 MEX message. The _pad variant
93 * strips leading zeroes from the b_key.
94 * Note that all numerics in the key token are big-endian,
95 * while the entries in the key block header are little-endian.
96 *
97 * @mex: pointer to user input data
98 * @p: pointer to memory area for the key
99 *
100 * Returns the size of the key area or negative errno value.
101 */
zcrypt_type6_mex_key_en(struct ica_rsa_modexpo * mex,void * p)102 static inline int zcrypt_type6_mex_key_en(struct ica_rsa_modexpo *mex, void *p)
103 {
104 static struct cca_token_hdr static_pub_hdr = {
105 .token_identifier = 0x1E,
106 };
107 static struct cca_public_sec static_pub_sec = {
108 .section_identifier = 0x04,
109 };
110 struct {
111 struct t6_keyblock_hdr t6_hdr;
112 struct cca_token_hdr pubhdr;
113 struct cca_public_sec pubsec;
114 char exponent[0];
115 } __packed *key = p;
116 unsigned char *temp;
117 int i;
118
119 /*
120 * The inputdatalength was a selection criteria in the dispatching
121 * function zcrypt_rsa_modexpo(). However, do a plausibility check
122 * here to make sure the following copy_from_user() can't be utilized
123 * to compromise the system.
124 */
125 if (WARN_ON_ONCE(mex->inputdatalength > 512))
126 return -EINVAL;
127
128 memset(key, 0, sizeof(*key));
129
130 key->pubhdr = static_pub_hdr;
131 key->pubsec = static_pub_sec;
132
133 /* key parameter block */
134 temp = key->exponent;
135 if (copy_from_user(temp, mex->b_key, mex->inputdatalength))
136 return -EFAULT;
137 /* Strip leading zeroes from b_key. */
138 for (i = 0; i < mex->inputdatalength; i++)
139 if (temp[i])
140 break;
141 if (i >= mex->inputdatalength)
142 return -EINVAL;
143 memmove(temp, temp + i, mex->inputdatalength - i);
144 temp += mex->inputdatalength - i;
145 /* modulus */
146 if (copy_from_user(temp, mex->n_modulus, mex->inputdatalength))
147 return -EFAULT;
148
149 key->pubsec.modulus_bit_len = 8 * mex->inputdatalength;
150 key->pubsec.modulus_byte_len = mex->inputdatalength;
151 key->pubsec.exponent_len = mex->inputdatalength - i;
152 key->pubsec.section_length = sizeof(key->pubsec) +
153 2 * mex->inputdatalength - i;
154 key->pubhdr.token_length =
155 key->pubsec.section_length + sizeof(key->pubhdr);
156 key->t6_hdr.ulen = key->pubhdr.token_length + 4;
157 key->t6_hdr.blen = key->pubhdr.token_length + 6;
158 return sizeof(*key) + 2 * mex->inputdatalength - i;
159 }
160
161 /**
162 * Set up private key fields of a type6 CRT message.
163 * Note that all numerics in the key token are big-endian,
164 * while the entries in the key block header are little-endian.
165 *
166 * @mex: pointer to user input data
167 * @p: pointer to memory area for the key
168 *
169 * Returns the size of the key area or -EFAULT
170 */
zcrypt_type6_crt_key(struct ica_rsa_modexpo_crt * crt,void * p)171 static inline int zcrypt_type6_crt_key(struct ica_rsa_modexpo_crt *crt, void *p)
172 {
173 static struct cca_public_sec static_cca_pub_sec = {
174 .section_identifier = 4,
175 .section_length = 0x000f,
176 .exponent_len = 0x0003,
177 };
178 static char pk_exponent[3] = { 0x01, 0x00, 0x01 };
179 struct {
180 struct t6_keyblock_hdr t6_hdr;
181 struct cca_token_hdr token;
182 struct cca_pvt_ext_crt_sec pvt;
183 char key_parts[0];
184 } __packed *key = p;
185 struct cca_public_sec *pub;
186 int short_len, long_len, pad_len, key_len, size;
187
188 /*
189 * The inputdatalength was a selection criteria in the dispatching
190 * function zcrypt_rsa_crt(). However, do a plausibility check
191 * here to make sure the following copy_from_user() can't be utilized
192 * to compromise the system.
193 */
194 if (WARN_ON_ONCE(crt->inputdatalength > 512))
195 return -EINVAL;
196
197 memset(key, 0, sizeof(*key));
198
199 short_len = (crt->inputdatalength + 1) / 2;
200 long_len = short_len + 8;
201 pad_len = -(3 * long_len + 2 * short_len) & 7;
202 key_len = 3 * long_len + 2 * short_len + pad_len + crt->inputdatalength;
203 size = sizeof(*key) + key_len + sizeof(*pub) + 3;
204
205 /* parameter block.key block */
206 key->t6_hdr.blen = size;
207 key->t6_hdr.ulen = size - 2;
208
209 /* key token header */
210 key->token.token_identifier = CCA_TKN_HDR_ID_EXT;
211 key->token.token_length = size - 6;
212
213 /* private section */
214 key->pvt.section_identifier = CCA_PVT_EXT_CRT_SEC_ID_PVT;
215 key->pvt.section_length = sizeof(key->pvt) + key_len;
216 key->pvt.key_format = CCA_PVT_EXT_CRT_SEC_FMT_CL;
217 key->pvt.key_use_flags[0] = CCA_PVT_USAGE_ALL;
218 key->pvt.p_len = key->pvt.dp_len = key->pvt.u_len = long_len;
219 key->pvt.q_len = key->pvt.dq_len = short_len;
220 key->pvt.mod_len = crt->inputdatalength;
221 key->pvt.pad_len = pad_len;
222
223 /* key parts */
224 if (copy_from_user(key->key_parts, crt->np_prime, long_len) ||
225 copy_from_user(key->key_parts + long_len,
226 crt->nq_prime, short_len) ||
227 copy_from_user(key->key_parts + long_len + short_len,
228 crt->bp_key, long_len) ||
229 copy_from_user(key->key_parts + 2 * long_len + short_len,
230 crt->bq_key, short_len) ||
231 copy_from_user(key->key_parts + 2 * long_len + 2 * short_len,
232 crt->u_mult_inv, long_len))
233 return -EFAULT;
234 memset(key->key_parts + 3 * long_len + 2 * short_len + pad_len,
235 0xff, crt->inputdatalength);
236 pub = (struct cca_public_sec *)(key->key_parts + key_len);
237 *pub = static_cca_pub_sec;
238 pub->modulus_bit_len = 8 * crt->inputdatalength;
239 /*
240 * In a private key, the modulus doesn't appear in the public
241 * section. So, an arbitrary public exponent of 0x010001 will be
242 * used.
243 */
244 memcpy((char *)(pub + 1), pk_exponent, 3);
245 return size;
246 }
247
248 #endif /* _ZCRYPT_CCA_KEY_H_ */
249